ww/test/wcc/852_variadic_body_reject.c

/*
 * 852_variadic_body_reject (C3) — cstage and wwstage LOUD-REJECT a
 * BODIED function whose param list ends in a bare C-style `...`, while
 * still ACCEPTING the bodiless extern/@symbol prototype (the real FFI
 * path) and the bodied Hare-style `T...` typed variadic.
 *
 * DIVERGENCE (rule 7/8): harec places NO bodiless restriction on C
 * variadism — a bodied C-variadic fn is legal in Hare because that is
 * where vastart/vaarg/vaend live (ref/harec/src/check.c:3656). ww ships
 * no va* builtins (task #16), so a bodied bare-`...` body could never
 * read its varargs — the construct is inexpressible. Gating it to
 * bodiless decls is therefore a sound ww-pragmatic restriction, NOT
 * "what Hare does"; when #16's builtins land this gate reopens.
 *
 * Pre-fix: cstage silently ACCEPTED a bodied bare-`...` fn (cmd/wcc/
 * check.c N_FNDECL pass-2 only guarded body==NULL); wwstage SEGFAULTED
 * (resolvefnbody walked a `...` param with no type). The fix adds, at
 * the N_FNDECL body-check site of each stage, a guard rejecting
 * (body != NULL && C-style variadic). The bare C-style param is the one
 * with str=="..."; Hare-style `T...` carries a name + op==TK_ELLIPSIS,
 * so it is unaffected. Bodiless decls keep flowing the FFI path.
 *
 *   row          | shape                                  | expect
 *   -------------+----------------------------------------+--------
 *   bodied_cvar  | fn f(x: i64, ...) void = {...}          | REJECT
 *   bodied_bare  | fn f(...) void = {...}                  | REJECT
 *   extern_cvar  | @symbol(..) fn ext(x: i64, ...) i64;    | BUILD, run 7
 *   hare_var     | fn sum(xs: i64...) i64 = {...}           | BUILD, run 7
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static int
runwait(const char *cmd)
{
	int rc = system(cmd);
	if (rc == -1) return -1;
	if (WIFEXITED(rc)) return WEXITSTATUS(rc);
	return -1;
}

static void
outbin(char *dst, size_t n, const char *tmpdir, const char *src)
{
	const char *base = strrchr(src, '/');
	base = base ? base + 1 : src;
	snprintf(dst, n, "%s/%s", tmpdir, base);
	char *dot = strrchr(dst, '.');
	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
}

/*
 * The reject must be the gate's clean diagnostic, not any nonzero exit:
 * the wwstage gate's absence reverts to a w6c SEGFAULT, which the driver
 * also wraps as a nonzero "w6c failed". Matching this shared diagnostic
 * substring distinguishes a loud reject from a crash, so the wwstage
 * reject rows are non-vacuous.
 */
static const char rejmsg[] =
    "C-style variadic '...' requires a bodiless declaration";

static int
filehas(const char *path, const char *needle)
{
	char buf[8192];
	FILE *f = fopen(path, "rb");
	if (!f) return 0;
	size_t n = fread(buf, 1, sizeof buf - 1, f);
	fclose(f);
	buf[n] = '\0';
	return strstr(buf, needle) != NULL;
}

static int
build_should_fail(const char *driver, const char *label, const char *src,
    int i)
{
	char s[128], tmpdir[64], cmd[1024], bin[128], errf[128], rmcmd[160];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/vbr_%d_d_%d", getpid(), i);
	mkdir(tmpdir, 0755);
	snprintf(s, sizeof s, "%s/vbr_%d_%d.ww", tmpdir, getpid(), i);
	snprintf(errf, sizeof errf, "%s/vbr_%d_e_%d.txt", tmpdir, getpid(), i);
	snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir);
	FILE *f = fopen(s, "wb");
	if (!f) { runwait(rmcmd); return -1; }
	fputs(src, f);
	fclose(f);
	outbin(bin, sizeof bin, tmpdir, s);
	snprintf(cmd, sizeof cmd, "%s build -o %s %s >/dev/null 2>%s",
	    driver, bin, s, errf);
	int rc = runwait(cmd);
	int hasmsg = filehas(errf, rejmsg);
	runwait(rmcmd);
	if (rc == 0) {
		fprintf(stderr, "vbr[%s][%s]: built ok, expected a reject\n",
		    driver, label);
		return -1;
	}
	if (!hasmsg) {
		fprintf(stderr, "vbr[%s][%s]: nonzero exit but missing gate "
		    "diagnostic (a crash, not a clean reject)\n", driver, label);
		return -1;
	}
	return 0;
}

static int
run_build(const char *driver, const char *label, const char *src, int i)
{
	char s[128], tmpdir[64], cmd[1024], bin[128], rmcmd[160];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/vbr_ok_%d_d_%d", getpid(), i);
	mkdir(tmpdir, 0755);
	snprintf(s, sizeof s, "%s/vbr_ok_%d_%d.ww", tmpdir, getpid(), i);
	snprintf(bin, sizeof bin, "%s/vbr_ok_%d_%d", tmpdir, getpid(), i);
	snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir);
	FILE *f = fopen(s, "wb");
	if (!f) { runwait(rmcmd); return -1; }
	fputs(src, f);
	fclose(f);
	snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null",
	    driver, bin, s);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "vbr[%s][%s]: build failed (valid variadic "
		    "must compile)\n", driver, label);
		runwait(rmcmd);
		return -1;
	}
	int got = runwait(bin);
	runwait(rmcmd);
	return got;
}

struct rejrow { const char *label; const char *src; };

static const struct rejrow reject_rows[] = {
	{ "bodied_cvar",
	  "package main;\n"
	  "fn f(x: i64, ...) void = { return; };\n"
	  "fn main() i32 = { return 0; };\n" },
	{ "bodied_bare",
	  "package main;\n"
	  "fn f(...) void = { return; };\n"
	  "fn main() i32 = { return 0; };\n" },
};

struct okrow { const char *label; const char *src; int want; };

static const struct okrow ok_rows[] = {
	{ "extern_cvar",
	  "package main;\n"
	  "@symbol(\"extfix\") fn extfix(x: i64, ...) i64;\n"
	  "fn main() i32 = { return 7; };\n",
	  7 },
	{ "hare_var",
	  "package main;\n"
	  "fn sum(xs: i64...) i64 = { return 0; };\n"
	  "fn main() i32 = { return 7; };\n",
	  7 },
};

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";
	char absbin[1024];
	if (bin[0] != '/') {
		char cwd[1024];
		if (getcwd(cwd, sizeof cwd) == NULL) return 1;
		snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
		bin = absbin;
	}

	char cdrv[1024], wdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	struct { const char *name; const char *path; int gated; } drivers[] = {
		{ "cstage",  cdrv, 0 },
		{ "wwstage", wdrv, 1 },
		{ NULL, NULL, 0 },
	};

	int nrej = (int)(sizeof reject_rows / sizeof reject_rows[0]);
	int nok = (int)(sizeof ok_rows / sizeof ok_rows[0]);
	int total = 0, fail = 0;

	for (int d = 0; drivers[d].name; d++) {
		if (drivers[d].gated && access(drivers[d].path, X_OK) != 0) {
			fprintf(stderr, "vbr: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].path);
			continue;
		}
		for (int i = 0; i < nrej; i++) {
			total++;
			if (build_should_fail(drivers[d].path,
			    reject_rows[i].label, reject_rows[i].src,
			    d * 100 + i) != 0)
				fail++;
		}
		for (int i = 0; i < nok; i++) {
			total++;
			int got = run_build(drivers[d].path, ok_rows[i].label,
			    ok_rows[i].src, d * 100 + i);
			if (got != ok_rows[i].want) {
				fprintf(stderr, "vbr[%s][%s]: exit=%d want=%d\n",
				    drivers[d].name, ok_rows[i].label,
				    got, ok_rows[i].want);
				fail++;
			}
		}
	}

	if (fail) {
		fprintf(stderr, "vbr: %d/%d fixtures failed\n", fail, total);
		return 1;
	}
	printf("vbr: %d/%d ok\n", total, total);
	return 0;
}